Copolymers of 2-substituted-1-acyloxybutadiene-1, 3 compounds



Patented Mar. 7, 1950 nits stares Ii Fi rce COPOLYMERS OFZ-SUBSTITUTED-l-ACYL- OXYBUTADIENE-L3 COMPOUNDS tion of New Jersey NoDrawing. Application February 9, 1946, Serial No. 646,708

2 Claims.

This invention relates to polymers of substituted l-acyloxy butadienesand to a process for their preparation. More particularly, it relates toco-- polymers obtainable by polymerizing a mixture of a l-acyloxybutadiene-1,3, wherein the 2-position is substituted by a halogen atom,an alkyl or aryl group, and one or more polymerizible monomeric vinylcompounds.

The copolymers of our invention are prepared by copolymerizing a dienehaving the general formula:

CH2=CH-(I3=CH-OCOR1 atom or groups, and R1 represents an alkyl, an

aryl group, a iuryl group, and a substituted alkyl group, for example,alkyl group substituted by a lower alkyl ether group or by one or morehalogen atoms, with a polymerizable monomeric vinyl compound, forexample, styrene or derivatives thereof, isobutylene, ethylene,butene-1,butene-2, butadiene, 2-chlorobutadiene, 2chloro-B-methylbutadiene, vinyl acetate, vinyl chloride, vinyl ketones,vinyl methyl ketone, vinyl alkylsullones, vinyl ethylsulfone, vinylsulfonamide, vinyl ethyl ether, amides, esters and half-nitriles offumaric and maleic acids, maleic imide, acrylonitrile,amethacrylonitrile and amides of acrylonitriles, vinyl urethanes andother similar kinds of monomeric unsaturated compounds. The abovedescribed copolymers are valuable intermediates for chemical reactions,and also as materials from which can be prepared useful coating andsheet forming compositions.

The polymerization reactions are promoted by means of heat, with orwithout a catalyst, and can be carried out in various manners. Forexample, the compounds to be copolymerized can be polymerized eitherwith or without the presence of an inert diluent such as heptane,benzene, acetic acid, dioxane, water or polymerized in the form of anemulsion or beads. The-process of polymerization takes place over a widetemperature range, but usually from about C. to about 200 (3., althoughtemperatures outside this range can also be employed. Pressures up toand in excess of 1000 atmospheres yield useful products. The reactingratio of the acyloxydiene compound to the vinyl compound is notcritical, since copolymeric products can be obtained with practicallyany ratio, the copolymers varying somewhat in properties in accordancewith the amount of the respective groups contained in the resinmolecule. The preferred resinous copolymers of the invention areobtained with starting mixtures having from about 5 to molecular partsof the specified acyloxydiene compound and from about 95 to 5 molecularparts of the monomeric vinyl compound. The catalyst can be an organicperoxide, for example, benzoyl peroxide, acetyl peroxide, urea peroxide,or inorganic catalysts such as boron trifiuoride, ammonium persulfate orother similar kinds of polymerization promoting compounds.

The intermediate acyloxydienes employed in practicing our invention canbe prepared, for example, by treating alpha-alkyl substituted oralpha-halo substituted crotonaldehydes or alpha and beta substitutedacroleins with isopropenyl acetate or with an organic acid anhydridesuch as acetic, propionic, butyric, benzoic, furoic, methoxyacetic,succinic, trifluoroacetic or trichloroacetic anhydrides, the product ineach case being the corresponding acyloxydiene derivative. Thepreparation of the 1-acyloxy-2-alkylbutadlenes are described and claimedin copending application in the name of J. B. Dickey and C. G.Stuckwisch, Serial No. 646,709, filed of even date herewith (now UnitedStates Patent 2,432,394, dated December 9, 1947). The alpha-halogenatedcrotonaldehydes can be prepared b the general method described in GermanPatent 559,329, the alpha-alkyl crotonaldehydes by the general methoddescribed in Canadian Journal of Research, 6 284 (1932), andalpha-alkylacroleins by the method described in Annalen, 434 1 45(1923).

It is, accordingly, an object of our invention to provide new copolymersof 2-substituted-l-acy1- oxybutadiene-1,3 compounds. Another object isto provide a method for preparing the same. Other objects will becomeapparent hereinafter.

The following examples will serve to illustrate our new polymers and themanner of their preparation.

Preparation of 1-acetoa:y-2-chZorobutadiene-1,3

105 grams of alpha-chloro crotonaldehyde, c. c. of acetic anhydride, 50grams of sodium acetate and 3 grams of copper acetate were heated on asteam bath for a period of about 8 hours and then poured into 250 c. c.of water and allowed to stand overnight. The lower heavy layer wasseparated, dried with anhydrous sodium sulfate and distilled. There wererecovered 30 grams of the unchanged alpha-chlorocrotonalde hyde in thefirst part of the distillate, and 40 grams ofl-acetoxy-2-chlorobutadiene-1,3 at 60-65? C. and at 25 mm. pressure inthe middle portion of the distillate. By substituting other anhydridesfor the acetic acid such as propionic, butyric,-benzoic,trifluoroacetic, trichloroacetic, and the like, there can be obtainedthe corresponding esters. In place of alpha-chlorocrotonaldehyde in theabove example.there can be substituted alpha-bromocrotonaldehyde oralphafluorocrotonaldeliyde to obtain diene esters corresponding to theseintermediates.

Example I.-PoZy-1-aceto:cy-2-methyl butadiene-1,3

3 grams of 1-acetoxy-z-methylbutadlene-1,3

, were placed in a sealed tube with 0.0003 gram of benzoyl peroxide. Thetube was placed in an oven at 110 C. fora period of about 3 weeks.Approximately 1 gram of the solid polymer was obtained.

Example II.Copolymer of I-acetory-Z-methyl butadiene-L3 and methylmethacrylate 1 gram (equiv. to 44 molecular parts) of methylmethacrylate and 1 gram (equiv. to 56 molecular parts) of1-acetoxy-2-methylbutadiene-1,3 were heated in a sealed tube at 50 C. inthe presence of benzoyl peroxide. After 24 hours heating there wasobtained one gram of the solid copolymer. Analysis of the product gave59.22 per cent by weight carbon and 8.60 per cent by weight of hydrogenas compared with theoretical of approximately 63.5 per cent carbon and8.0 per cent hydrogen. According to this analysis, 93.4 per.

cent by weight of the theoretical amount of carbon is accounted for, andif the higher hydrogen found is assumed to be partly due to water, thenthe value of the carbon accounted for approaches closer to 100 per centtheoretical. The analysis indicates, therefore, that the productobtained was substantially a copolymer of 1-acetoxy-2- methylbutadiene-l,3 and methyl methacrylate, the units of the respectivecompounds being present in the polymer molecule in the approximateproportions of the starting mixture of monomeric compounds.

In a similar manner, and by substituting other vinyl compounds in placeof the methyl methacrylate in the above example, there were obtainedwith acrylonitrile a copolymer which was mostly insoluble in acetone,but yielded on extraction 10 per cent resin soluble in acetone; withisopropyl methacrylate at 50 C., a. yield of about 50 per cent of thecopolymer corresponding thereto; and with N,N-diethyl acrylamide at 110C. a yield of about 30 per cent of solid copolymer.

Example III .Cpolymer of I-propionoxy-Z- phenylbutadiene-1,3 and vinylchloride 8 grams (equiv. to 55.3 molecular parts) of 1-propionoxy-Z-phenyl butadiene-1,3 and 2 grams BX were shaken together.

(equiv. to 44.7 molecular parts) of vinyl chlo- Example IV.C'opolymer of-1-acetoxy-Z-chlorobutadiene-1,3 and acrylonitrile 15 grams (equiv. to26.6 molecular parts) of 1- acetoxy-2-chlorobutadiene-1,3, 15 grams(equiv. to 73.4 molecular parts) of acrylonitrile and .1 gram benzoylperoxide were polymerized at 60 C. in a nitrogen filled tube. Thepolymerization was complete in about 4 days. The tough elastic productobtained had a ratio or 1 part or the diene radicals to 2 parts of theacrylonitrile radicals in the molecule. In place of a-methylacrylonitrile, there can be substituted in the above example, methylmethacrylate N-butyl maleic imide, a-methyl acrylonitrile or a-ChlOIO-acrylonitrile to obtain similarly useful resinous solids.

Example V.--Copolymer of l-propionozcy-Z- bromobutadiene-1,3 and vinylchlorzde 15 grams (equiv. to 5.1 molecular parts of1-propionoxy-2-bromobutadiene-1,3, 85 grams (equiv. to 94.9 molecularparts) of vinyl chloride, 3.5 grams of sulfonated oleic acid, 2.0 gramsof methyl cellulose, 2.8 grams of benzoyl peroxide and 275 c. c. ofwater were mixed into an emulsion, and polymerized at 55-60 C. for aperiod of about seven days. The polymer was isolated from the reactionmixture by precipitation with ammonium sulfate.

Example VI.-Copolymer of Z-acetozy-Z-chloro- 'butadiene-L' andisobutylene 2 grams (equiv. to 1.5 molecular parts) 1-acetoxy-2-chlorobutadiene-1,3, and 50 grams (equiv. to 98.5 molecularparts) of isobutylene were polymerized at 50 to C., using borontrifluoride. A tough vulcanizable polymer was obtained. In place of1-acetoxy-2-chlorobutadiene-1,3, there can be substituted in the aboveexample other diene compounds, for example, 1 acetoxy 2 fluorobutadiene1,3, l-acetoxy- 2-methylbutadiene-1,3, 1-acetoxy-2-ethylbutadiene-1,3,1-acetoxy-2-phenyl butadiene-1,3, or 1-acetoxy-2-p-anisyl butadiene-1,3.

Example VII .-Copolymer of l-acyloxydienes and butadiene 25 grams(equiv. to 62.1 molecular parts) of 1- acetoxy-2-methylbutadiene-2,3,25grams (equiv. to 37.9 molecular parts) 1-benzoyl-2-chlorobutadiene-1,3,250 c. 0. water and 5 grams of Nekal Then 1.4 grams of sodiumpyrophosphate, 4 grams of gelatin, 0.2 gram of amyl alcohol and 0.8 gramof sodium persulfate were added. The mixture was stirred at about 55 C.,until emulsification was complete. The rubber-like polymer was isolatedby precipitation with ammonium sulfate.

Example VIIL-Copolymer of I-acetoxy-Z-methylbutadiene-1,3 and ethylene 1gram (equiv. to 45 molecular parts) of 1- acetoxy-2-methylbutadiene-1,3and 3 grams (equiv. to 55 'molecular parts) of ethylene were chargedinto an autoclave and slowly heated until a temperature of about 200 C.,and a pressure of about 3000 atmospheres was reached. Nitrogen was usedas booster gas. A tough, vulcanizable elastomer was obtained. In placeof ethylene, there can be substituted in the above example propylene,butene-l or butane-2.

The copolymers of the above examples are thermoplastic elastomers whichcan be extruded in the form of wires, rods, tubes, and sheets, or moldedby compression or injection processes.

5 Fillers, coloring materials and plasticizers can be added. In theusual practice, the polymer is first softened by heat or chemicalsoftening agents, flllersadded as desired, and then kneaded,

rolled, vulcanized, compressed or drawn under 26.6-molecular parts ofl-acetoxy-Zwhlorobutadiene- '1,'3fand 73.4 molecular parts ofacrylonitrile. the said diene compound and said acrylonitrile being thesole polymerizable compounds in the mixture.

JOSEPH B. DICKEY. NORMAN J. BOWMAN. CLARENCE G. STUCKWISCH.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS is Number Name Date 2,073,363 Carothers Mar. 9,1937 2,195,382 ISlagh Mar. 26, 1940 2,432,460 Unruh e Dec. 9, 1947

1. A COPOLYMER DERIVED BY THE POLYMERIZATION OF A MIXTURE OF 26.6MOLECULAR PARTS OF 1-ACETOXY2-CHLOROBUTADIENE-1,3, AND 73.4 MOLECULARPARTS OF ACRYLONITRILE, THE SAID DIENE COMPOUND AND SAID ACRYLONITRILEBEING THE SOLE POLYMERIZABLE COMPOUNDS IN THE MIXTURE.